Forecasts project that, by 2050, there will be 9.6 billion people on the planet and that we will lack enough water resources around the world to sustain current consumption patterns. Seawater desalination, the only man-made process that generates new freshwater resources, is thus becoming increasingly important for the future of humanity. Today, an estimated 75 million people worldwide rely on seawater desalination for meeting their drinking water needs, and the figure is increasing at rate of approximately 10% annually. However, seawater desalination has an environmental impact. Every day, about 100 billion liters of seawater flows in to a desalination plant and 50 billion liters of salty brine is discharged in to the sea. Desalination brine discharged into the sea can adversely affect the marine environment near the discharge sites. One method of mitigating this negative impact is zero-discharge seawater desalination, where desalination brine is further concentrated to produce pure salt and additional drinking water.
Stand-alone electrodialysis (ED) systems have been deployed in Japan or concentrating seawater to produce salt. One of the biggest drawbacks hindering the adoption of ED technology for brine concentration has been the high capital costs of the system with the main market for the technology being limited to Japan currently.